feat: use chmod flag during COPY

[greut]

The extra chmod step can be carried out by Docker itself. It requires buildkit mode to be on, but it's the case when using buildx.

[jpkrohling]

Are you facing a specific problem leading to this change?

[greut]

Not at all, as I've been rebuilding it locally for #204, this bit got me surprised and felt it was an opportunity to remove a comment pointing to an old issue, open-telemetry/opentelemetry-collector#1317

[jpkrohling]

Before merging, can you positively confirm that you built an image with this new Dockerfile and it worked as expected?

[greut]

I've pushed a fake release over there from that branch + the related changes in goreleaser.

• https://github.com/greut/opentelemetry-collector-releases/pkgs/container/opentelemetry-collector-releases%2Fopentelemetry-collector
• https://github.com/greut/opentelemetry-collector-releases/pkgs/container/opentelemetry-collector-releases%2Fopentelemetry-collector-contrib

[jpkrohling]

@open-telemetry/collector-maintainers, @open-telemetry/collector-contrib-maintainer, this has the potential to break the release, but I believe it will not. In the worst case, the binaries in the generated images won't have the execute flag, preventing the binary from running.

In any case, my message to the next person in line to perform the release (@dmitryax?): keep this issue in mind if anything fails during the release process.